Apparatus for finishing packing rings



Nov. 8, 1949 M. E. L PEZOUS 2,487,670

APPARATUS FOR FINISHING PACKING RINGS 2 Sheets-Sheet 1 Filed June 4, 1946 Nov. 8, 1949 M. E. L. PEZOUS 2,487,670

APPARATUS FOR FINISHING PACKING RINGS Filed June 4, 1946 2 Sheets-Sheet 2 Patented Nov. 8, 1949 UNITED STATES PATENT OFFICE Maurice E. L. Pezous, Albi, France Application June 4, 1946, Serial No. 674,287 In France July 10, 1939 Section 1, Public Law 690, August 8, 1948 Patent expires July 10, 1959 4 Claims.

The present invention relates to the manufacture of piston rings having recti inear cuts and it is more especiallv concerned with the finishing of said cuts by filing or grinding of the sides thereof.

Up to now, this finishing operation was generally performed manually, requiring much skill and attention from the workmen. so that the output was low, without giving any certainty of obtaining the precision and uniformity that are necessary if the packing rings are to play the part for which they are intended.

Furthermore, these methods involved risks of breaking or deteriorating the packing rings.

The object of the present invention is to provide an apparatus for mechanically performing the finishing operation and thus avoiding all the drawbacks above mentioned.

According to my invention, this apparatus essentially includes a frame having a plane surface for supporting the circular edge of a packing ring, with means, preferably adjustable, for positioning said packing ring on said surface, and means, also preferably adjustable, for guiding the movement of a filing or grinding tool with respect to said frame so as automatically to obtain the desired action of said tool on the packing ring held in position on said flat surface of the frame.

Preferred embodiments of my invention will be hereinafter described, with reference to the accom anying drawings, given merely by way of example, and in which:

Fig. i is an elevational view of an apparatus according to my invention made according to a first embodiment thereof;

Fig. 2 is a plan view corresponding to Fig. 1;

Figs. 3 and 4 are views. similar to Figs. 1 and 2, respectively, corres onding to a second embodiment of my invention.

As shown by the drawings, the apparatus in cludes a frame I the top face of which is plane so as to support the circular edge of a packing ring 1'. Two positioning members 3 are freely pivoted to said frame about axes perpendicular to said top face and materialized by the stems of knurled nuts 4, so that said members 3 can pivotally slide on said top face. The active edges of said members 3 form, in plan view, reentrant obtuse angles of equal values, advantageously rather great. In transverse section, said edges make with the top face of the frame an angle slightly smaller than 90, so as to keep piston ring 1' applied against said face of the frame.

Opposite these two members 3 is located a third analogous member 5 provided with a downward projection slidable in a groove 6 of the frame. This member 5 is actuated by means of a lever I through a spindle screwed on member 5 and slidable in an oval slot 8 of lever I. This third jaw member 5 carries at its rear part a threaded rod 9 extending through an aperture provided in frame I; on this threaded rod is screwed a knurled nut Ill adapted to be secured in position by a lock nut, also knurled, which permits of adjusting the position of member 5 for a given category of packing rings. The end of lever 7 is pivoted to the stem of a bolt II which can be adjustably fixed in a groove I2 of the frame so as to permit the finishing of packing rings of difierent diameters.

Referring now more particularly to the embodiment of Figs. 1 and 2, a file I3 of suitable thickness is mounted in a support constituted by two end pieces I4 and I5 and longitudinal rods I6 and IT for connecting said pieces together. Rods I6 and I1 are slidably guided in two annular elements I8 and I9 adjustably carried by bearings 2 mounted in frame I.

Each bearing 2 is constituted by a kind of collar slit at 2a. Screws 20 engaged in the portions of the collar on either side of the ga permit of tightening said collar around annular element I8 or I9, after said element has been given the desired angular position. The file can thus be guided in any desired plane with respect to frame l.

This apparatus will be used as follows:

The workman places the packing ring to be finished in contact with oscillable jaw members 3 so that the gap in the packing ring coincides with the plane in which file I3 is guided.

Bolt II is then secured in groove I2 in a position such that when the packing ring 1' is tightly held between jaw elements 3 and 5, lever I is substantially at right angles to the direction of groove 6. The plane in which the file support i4, I5, I6, I! is guided has been determined as above explained (adjustment of pieces l8 and I9 in collar 2).

The packing ring 1* to be finished is first brought into contact with jaws 3; then lever I is pivoted about bolt I I, so as to apply jaw element 5 against the packing ring until the two faces of the cut in the packing ring bear against the opposed sides of the file, respectively.

At this time, while keeping the packing ring thus tightly held, the operator reciprocates the file with his free hand for finishing the faces of the cut in the packing ring. Due to the inclination of the active faces of jaw elements 3, packin ring r remains applied against the frame.

If a great number of identical packing rings are to be finished on the apparatus, the forward moveme t of iaw element 5 is limited by means of knurled nut I and its lock nut.

In the embodiment of my invention shown by Figs. 3 and 4, the general arrangement is the same as above described concerning the frame and the means for positioning the packing rings thereon. But the tool for finishing the faces of the cut is rotary tool (grinding wheel or milling cutter) instead of a file.

This rotarytool 24 is mounted in a cast iron or sheet metal casing 2|. A pair of cooperating bevel pinions 22 is journalled in this casin one of these pinions being driven by the operator by means of a crank 3, while the other is keyed on the spindle of the milling cutter or grinding wheel 2| This tool passes freely in a slot 25 provided in A frame 1.

Casing 2I is angularly adjustable on frame I and carries at its lower part a guiding band; it can be fixed at will by means of two nuts 21 in a graduated groove provided in the frame.

Su table markin s along this groove permit of adjusting the position of easing 2| along frame I accordin to the desired cutting angle.

The working of this apparatus is the same as above described.

Casing 2| being placed at a suitable angle. the o erator t htens n ts 21. The packing ring r to be fin shed is held between jaw elements 3 and 5, lever 1 being pulled so that the two ends of the packin ring (1. e. the faces of the cut thereof) bear against the respective sides of rotary tool 4.

The operator then operates crank 23 so as to rotate the rotary tool at a speed sufficient for obtaining a suitable finishing of the packing ring cut.

In this embodiment, as the middle part of frame I is unobstructed by elements such as part ll of Fig. 2, jaw element 5 can be brought to a shorter distance from elements 3, and groove I2 is accordin ly much longer than in the preceding embodiment.

In a general manner, while I have, in the above descri tion, disclosed what I deem to be practical and eiiicient embodiments of the present invention, it should be well understood that I do not wish to be limited thereto as there might be changes made in the arrangement, disposition and form of t e parts without de arting from the principle of the present invention as comprehended within the scope of the accompanying claims.

What I claim is:

1. An apparatus for finishing the cuts of packing rin s which comprises, in combination. a frame having a flat surface for su porting the circular edge of a packing ring, a finishing tool movable in a plane with respect to said frame. means for guiding the movement of said tool with respect to said frame, two angular jaw elements freely pivoted to said frame about respective axes perpendicular-to said surface located on either side of the plane of movement of said tool, the active edges of said jaws forming, in plan view, reentrant obtuse angles of equal value and making, in transverse section, an angle smaller than with said flat surface, so as to keep said packing rings applied against said flap surface, and a third jaw element slidable on said surface in the direction of the above mentioned plane of movement of said tool.

2. An apparatus for finishing the cuts of packing rings which comprises, in combination, a frame having a flat surface for supporting the circular edge of a packing ring, a finishing tool movable in a plane with respect to said frame, means for guiding the movement of said tool with respect to said frame, two angular jaw elements freely pivoted to said frame about respective axes perpendicular to said surface located on either side of the plane of movement of said tool, the active edges of said jaws forming,.in plan view. reentrant obtuse angles of equal value and making, in transverse section, an angle smaller than 90 with said flat surface, so as to keep said packing rings applied against said fiat surface, a third jaw element slidable on said surface in the direction of the above mentioned plane of movement of said tool, and a lever pivoted to said frame about an axis perpendicular to said surface, said lever being slidably connected with said third jaw to permit relative movement of said third jaw and said lever in a direction transverse to said plane.

3. An apparatus for finishing the cuts of packing rings which comprises, in combination, a frame having a flat surface for supporting the circular edge of a packing ring, a finishing tool movable in a plane with respect to said frame, means for guiding the movement of said tool with respect to said frame, two angular jaw elements freely pivoted to said frame about respective axes perpendicular to said surface located on either side of the plane of movement of said tool, the active edges of said jaws forming, in plan view, reentrant obtuse angles of equal value and making, in transverse section, an angle smaller than 90 with said fiat surface, so as to keep said packing rings applied against said flat surface, a third jaw element sliciable on said surface in the direction of the above mentioned plane of movement of said tool, a lever pivoted to said frame about an axis perpendicular to said surface, said lever being slidably connected with said third jaw to permit relative movement of said third jaw and said lever in a direction transverse to said plane, and adjustable means for limiting the displacement of said third jaw toward said tool.

4. An apparatus according to claim 2 further including means for adjusting the position on said frame of the axis about which said lever is pivoted to said frame.

MAURICE E. L. PEZOUS.

' REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Wilsey Sept. 3, 

